Long range rendering.

[Hungry4info]

If we only render an object when it's angular size is > one pixel (or whatever the lowest rendering for Celestia is), then is it possible for Celestia to not even show objects that are invisible? If I go out to ~500 AU, I can still click into random places in the Sol system and select some random asteroid somewhere. This isn't exactly a major limitation, but this leads me to my next point.

If we only allow objects to "exist" when their angular size is > then the minimum size, then is it possible we could eliminate the problem of no objects being visible if it's more than a light year from it's star? Objects too small (in angular size) to be visible aren't rendered. This way, in theory, I could sit in the Sol system, zoom in (decrease FOV) on Gliese 876 (for example) and see the three orbital paths of it's known planets. I figure this will add some consistancy to Celestia and make it "smoother".

It's rather akward to be approaching Betelgeuze or Antares at full zoom and see it instantly "pop" into a star once I'm closer than 1 ly.

Any thoughts?

[chris]

If we only render an object when it's angular size is > one pixel (or whatever the lowest rendering for Celestia is), then is it possible for Celestia to not even show objects that are invisible? If I go out to ~500 AU, I can still click into random places in the Sol system and select some random asteroid somewhere. This isn't exactly a major limitation, but this leads me to my next point.

There's already a bug on the SourceForge tracker for this problem. It will get addressed.

If we only allow objects to "exist" when their angular size is > then the minimum size, then is it possible we could eliminate the problem of no objects being visible if it's more than a light year from it's star? Objects too small (in angular size) to be visible aren't rendered. This way, in theory, I could sit in the Sol system, zoom in (decrease FOV) on Gliese 876 (for example) and see the three orbital paths of it's known planets. I figure this will add some consistancy to Celestia and make it "smoother".

It's rather akward to be approaching Betelgeuze or Antares at full zoom and see it instantly "pop" into a star once I'm closer than 1 ly.

Any thoughts?

I don't know how to make it possible to zoom in on a distant star system. The single precision arithmetic tends to break down at such narrow fields of view. Celestia could switch to double precision math on the CPU in these cases, but it would be a lot of work. I will try and do something about large stars though. The problem there is that Celestia assumes anything over one light year distance will be visible only as a point. I could change this to make the distance threshold dependent on the field of view.

--Chris